The children's Hospital, Denver, has participated in CCSG as a full member since 1980. During that period we have participated in all group wide clinical trials and have consistently been in the top half of institutions in terms of numbers of patients entered on CCSG protocols. Despite our relative youth within the Group, Denver is contributing to the scientific expertise of the group by providing leadership in a number of areas. We have seven memberships on five cancer strategy groups. Our faculty chairs the largest CCSG clinical study (study (CCG-105) and provides the vice- chairman for a non-Hodgkin"s lymphoma protocol (CCG-502), a proposed NHL retrival protocol (CCG-554) and a proposed front line strategy groups or open or proposed clinical trial committees. In addition, we have representatives on the various discipline committees and one of our members is vice-chairman of the Surgery Committee while another is chairperson of the Nursing Committee. The principal investigator also is a member of the Group Membership Committee and Group Executive Committee. The Children's Hospital, Denver has brought to the group concepts in the areas of Pharmacology, induction therapy of acute non- lymphoblastic leukemia and the treatment of infantile monoblastic leukemia which have subsequently been developed on a group wide basis. We were invited as one of four CCSG institutions to Participate with the National Cancer in a trial of very high dose methotrexate because of our interest and recognized expertise in sophisticated supportive care. We are currently conducting a single institution study with LAK cells and lL-2 for recurrent brain tumors which has received a CCSG special study designation. Since 1980 we have had an interest in intra operative irradiation for non-resectable solid tumors and have experience with twenty- three patients so treated. This data is being evaluated by the CCSG Radiation Therapy Committee for possible group wide introduction. On a local level we have developed a data management section which consistently ranks as one of the best in CCSG and we have served as advisors and consultants to other CCSG institutions and potential members. Our institution has been audited twice, once with an NCI observer, for compliance to research requirements with no deviations found from the federal regulations.